Emergency room patients are an important resource for examining the contribution of alcohol misuse to illness and injury (SHHS, 1993). Thailand has significant public health problems related to alcohol abuse and has an infrastructure that will support the proposed study. During my proposed sabbatical in Thailand I will conduct a survey of consecutive patients presenting to hospital ERs in each of Thailand's four regions. The survey will consist of self-report questionnaires and breathalyzer tests. The objectives of the proposed study are: 1) to develop an estimate of the prevalence of potentially harmful alcohol use among persons treated at regional ERs in Thailand. This will be accomplished using a 10-item screening test, the AUDIT (Babor et al.. 1989), which was developed by the World Health Organization (WHO) to identify persons at high risk for alcohol-related illness and injury. Concurrent validity will be examined by comparing AUDIT scores with medical record and breathalyzer data (Babor et al., 1989); 2) to compare trauma and nontrauma patients with regards to the percentage of persons with positive breath alcohol levels (BACs); and 3) using the subset of trauma patients, to classify the cause of injury according to BAC. self-report of alcohol involvement, and AUDIT scores. Data gathered in the proposed investigation will provide important information that will be useful in estimating the role of alcohol in injuries in Thailand and determining the need for ER-based alcohol screening and intervention programs.